PROJECT SUMMARY/ABSTRACT Children obtain more mental health services through schools than through any other public system or agency. In Philadelphia, similar to many other urban school districts, school-based mental health care often is provided by school therapeutic support (STS) teams. The Philadelphia STS model, a common school-based mental health model, shares features with community mental health team models. In an effort to improve STS services in Philadelphia, the Philadelphia Department of Behavioral Health has contracted with the Beck Initiative to provide lead clinicians with extensive training and consultation in the broad application of cognitive- behavioral therapy (CBT), including for disruptive behavior disorders. STS clinicians may struggle to implement CBT due in part to challenges obtaining support from other members of the STS team. Current training models focus on EBP training for clinicians and neglect the functioning of the teams they operate within. This overall lack of attention to the broader team system may be contributing to failure to use EBPs in schools, as training alone has been shown to be insufficient. Participants for the proposed study will be drawn from STS teams in the Philadelphia community mental health network. In collaboration with stakeholders, Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPS), an evidence-based approach for improving team functioning in health care settings, will be adapted for use with school mental health teams. Second, the adapted TeamSTEPPS will be pilot tested. Feasibility and acceptability of the adapted TeamSTEPPS approach, as well as the impact of the approach on team skills and behavior, will be assessed. Teams of STS paraprofessionals and clinicians in two schools participating in an ongoing implementation of CBT in Philadelphia will receive the adapted TeamSTEPPS approach, to be compared with two schools in which the lead clinicians receive CBT training as usual without TeamSTEPPS. Mixed methods will be used to examine contextual predictors of implementation, such as implementation climate, organizational readiness for change and attitudes toward teamwork in STS teams and their relationship to feasibility and acceptability. This project extends our understanding of strategies to improve EBP implementation among school-based mental health care teams and has broader implications for mental health treatment teams in other settings such as community mental health. The proposed research will coincide with advanced training opportunities and mentorship to develop expertise in implementation science.